1. Field of the Invention
The present invention relates to an image forming apparatus including a toner container into which a toner is replenished after the toner has been exhausted.
2. Description of the Related Art
An image forming apparatus forms a visible image developed with a toner in accordance with image information. Then, the visible image is transferred onto recording paper. A process cartridge includes a toner holding portion that holds the toner therein. As the images are formed more and more, the toner is consumed more and more.
Some image forming apparatuses are provided with a detecting means for detecting that an amount of toner remaining in the image forming apparatus is more than a reference value. The detecting means may be incorporated in a toner bottle to detect the amount of toner in the toner bottle. Alternatively, the detecting means may be incorporated in a process cartridge to detect the amount of toner in the process cartridge or a toner bottle (see Japanese Patent Application Laid-Open Nos. H09-236982 and 2003-50505).
Also, there has been proposed a technology that employs a restricting means for restricting the supply of toner from a toner bottle to a process cartridge, a memory for recording the usage of the toner in terms of the number of printed dots, and a detecting means provided in the process cartridge for detecting the remaining amount of toner. The combination of the detection output of the detecting means and the recorded usage of the toner informs a user of the time for the toner bottle to be replaced (see Japanese Patent Application Laid-Open No. 2006-267528).
However, the image forming apparatus including the detecting means disclosed by Patent Application Laid-Open No. H09-236981 suffers from a problem in that the remaining amount of the toner in the toner bottle may not be accurately detected. The image forming apparatus disclosed by Patent Application Laid-Open No. 2003-50505 suffers from a problem that incorporating the detecting means leads to increased cost of the toner bottle.
The apparatus disclosed by Patent Application Laid-Open No. H09-236982 requires a toner supply restricting means such as a shutter for restricting the supply of toner from the toner bottle into the process cartridge. The provision of a shutter involves a mechanism for opening and closing the shutter, leading to increased cost of the apparatus.